Non-peelabel  insole and manufacturing method

ABSTRACT

An insole of the present invention includes a first layer, and a second layer integrally and continuously formed with the first layer. The second layer is mold-injected on the first layer to bond the second layer with the first layer, so as to form the stable bonding therebetween for securely and integrally bonding the first and second layers in a glue-less manner.

BACKGROUND OF THE PRESENT INVENTION

1. Field of Invention

The present invention relates to an insole of a shoe, and moreparticularly to a non-peelable insole, wherein the non-peelable insolehas a first layer integrally and continuously formed with a secondlayer, such that the first and second layer are firmly attached witheach other to form the non-peelable insole.

2. Description of Related Arts

Most of the shoes have an insole, which normally has an upper layer anda lower layer attached to the upper layer by glue, and the lower layermay be provided as a cushion layer for enhancing the comfortablenesswhen the user is wearing the shoe, while the upper layer may provide asmoothie surface for being directly contacted with the user's feet, soas to provide different designed graphics thereon within the shoe cavityfor replacing on the bottom shoe sole. The China Patent application,which has an application number of 200410026765, has published a processof making the shoe insole. This invention disclosed the upper layer ofthe shoe insole is made by forming a center piece of the upper layer anddisposing the center piece in a center portion of a cavity of the mold.Then, the injection material, which is PU material, is injected into thecavity of the mold such that the injection material is outwardlyextended from the center piece and is formed at the outer peripheralportion of the upper layer. Accordingly, the center piece of the upperlayer is made of EVA material treated with foaming process and precutinto a predetermined shape. Alternatively, the center piece can beflattened and precut into the predetermined shape.

Traditionally, the insoles are made by a process comprises the steps ofproviding a sheet of the first layer, such as PU layer (polyurethane),and a sheet of the second layer, such as PVC layer (polyvinyl chloride),cutting the sheet of the first and second layers to a desired shape inaccordance to each other, alignedly gluing the first and second layersof the cut sheets, and pressing the corresponding first and secondlayers of the cut sheets to firmly glue with each other and drying thefirst and second layers of the cut sheets, so that the insole is formed.However, the insole commonly made by the above mentioned process has theplurality of drawbacks.

Firstly, the process of separately forming, tailoring, and gluing thetwo layers, such as the PU layer and PVC layer, requires a great amountof work by human, so that it is time consuming and inefficient.

Secondly, some traditional process of making insole glues the two layerof the insole before tailoring the two layers thereof, so that theefficiency of the process is slightly increased. However, the pre-gluedtwo layers of insole require a large amount of glue, which is materialwaste and rising another the environmental issue of the pollutant ofglue. Further more, the large gluing surface between the two layers ishard to control the amount of the glue, so as to reduce the quality ofthe insole.

Third, the sheets of first and second layers are trimmed or cut to apredetermined shape for fittedly accommodated within the bottom sole ofthe shoe, so that only the cut parts of the cut sheets are used formaking the insole. The other non-cut parts of the cut sheets are wasted.

Fourth, in order to align the cut sheets of the first and second layersfor being bonding therewith via glue, a predetermined accuracy of thealigning step for attaching the cut sheets of first layer to the secondlayer is required for the perfect looking of the insole. The amount ofglue is hard to evenly apply thereon, so that partial of the first andsecond layers are insecurely attached with each other, so as to reducethe quality of insole.

Fifth, the manually glued first and second layers are easily detachedapart from each other during the washing or cleaning process of theinsole, so as to decrease the life time of the insole.

Sixth, the glue used in the process usually has the property ofvolatile, so that the toxicity of the glue may be easily evaporated inthe air, so as to harm the health and pollute the environment.

On the other hand, the present invention is preferably making the insolewith the TPR material, which is made of thermoplastic material, has bothcharacteristics of rubber and thermoplastic material, such that thistype of material has the processability of thermoplastic and thephysical properties of vulcanized rubber. The second layer is also madeof cushioning material for providing a cushion effect of thenon-peelable insole pad. Moreover, the TPR material is able to beprocessed by the traditional plastic material processing equipmentswithout vulcanizing, so as to provide a relatively more environmentalfriendly product.

SUMMARY OF THE PRESENT INVENTION

An object of the present invention is to provide an insole and itsmanufacturing method of integrally forming the first and second layersby mold injection in order to improve the above mentioned shortages ofexisting art.

Accordingly, in order to accomplish the above objects, the presentinvention provides an insole, which comprises a first layer, embodied asPU layer, and a second layer, embodied as TPR layer, integrally andcontinuously formed with the first layer preferably by thermoplasticprocess. In particular, the present invention provides an insole, whichis non-peelable for enhancing the durability of the insole. Accordingly,the bonding between the first and second layer of the insole isrelatively strong, so that after bending, heating, or soaking the insolein water, the first and second layers are not separated from each other.In addition, no complicated alignment is involved for bonding the firstand second layers of the insole, so as to simplify the manufacturingprocess of the insole.

Another object of the present invention is to provide an insole, whereinno glue is required for bonding the first and second layer of theinsole, so as to provide a relatively more eco friendly product.

Another object of the present invention is to provide an insole, whereinthe injected second layer of the insole minimizes the waste of rawmaterial.

Another object of the present invention is to provide a method of makingthe insole, wherein the method significantly increases the productivityand efficiency of manufacturing process of insole, so as to minimize themanufacturing cost.

Another object of the present invention is to provide a method of makingthe insole, which does not require to alter the original structuraldesign of the insole, so as to minimize the manufacturing cost of theinsole with the integrated structure.

Another object of the present invention is to provide a method of makingthe insole, wherein no expensive or complicated structure is required toemploy in the present invention in order to achieve the above mentionedobjects. Therefore, the present invention successfully provides aneconomic and efficient solution for providing an integratedconfiguration for the insole.

The present invention also provides a method for making the insole,wherein the method comprises the following steps.

(a) Cut a first sheet to form a plurality of first layers of an insole.

(b) Dispose the first layers into a sealing cavity of the insole mold,and enclose the first layer within the sealing cavity.

(c) Inject an injection material of the second layer at a fluid state,which is embodied as TPR material, wherein the injection material isinjected into the sealing cavity of the insole mold to evenly dispenseon the first layer. It is worth mentioning that a thickness of thesecond layer is selectively adjusted by a volume of the fluid materialof the second layer. After the injection material is cooled down, theTPR as the injection material is formed a predetermined shape of theinsole in accordance with the first layer and to bond with the firstlayer, which is embodied as PU layer. In other words, the first layer isbonded with the second layer through the thermoplastic formation.

(d) Open the sealing cavity of the insole mold to remove the finalproduct of the non-peelable insole.

In the step of injecting the fluid injection material of the method ofmaking the insole, the injecting temperature is between 150° C. and 300°C.

In the method of making the insole, the insole mold comprises a firstmolding body having a first molding cavity and a second molding bodyhaving a second molding cavity, wherein the first layer is disposedwithin the first molding cavity, wherein said injection material ininjected into the second molding cavity through an injection channelthereat.

Therefore, the present invention eliminates the trimming process of thesecond material, which embodied as TPR material, and the process ofmanually gluing the first layer embodied as PU layer and the secondlayer, so as to enhance the efficiency of producing the insole. Thefirst layer of the PU material and the second layer of the second layerof the TPR material are bonded under high temperature, so that the firstand second layers are able to be firmly and securely attached to eachother, so as to prolong the life time of the insole. Furthermore, thepresent invention is able to efficiently utilize the TPR or otherinjection source of the second material, so as to minimize the originalmaterial cost to minimize the unnecessary waste of material. The TPRmaterial is also recyclable, so as to meet the environmental friendlyrequirement.

Accordingly, the second layer is integrally bonded with the first layerto form the non-peelable insole with the following advantages.

Perfect bounding: By injecting the fluid material of the second layer tobond with the first layer via a relatively strong bonding in comparisonwith the glue, the first and second layers will not be separate afterwearing, bending, heating, washing, or soaking the insole.

Environmental friendly: The first and second layers are bonded togetherwithout the use of glue. As it is mentioned above, the glue is achemical compound having the property of volatile, so that the toxicityof the glue may be easily evaporated in the air, so as to harm thehealth and pollute the environment.

Better appearance: Since the second layer is injected on the firstlayer, the second layer will perfectly align with the first layer. Asthe conventional glue method, the second layer is cut and is required toalign with the first layer in order to glue the second layer on thefirst layer. Therefore, the conventional insole must be trimmed its edgeto keep the clean edge.

Clean appearance: No glue seam between the first and second layers isformed. Accordingly, with the conventional glue method, the glue seambetween the first and second layers is virtually impossible toeliminate.

Product expansion ability: With the injection method of the presentinvention, the material of the first layer will not be limited as PUonly. In other words, other materials can be used for the first layer tointegrally bond with the second layer. However, the conventional gluemethod can only apply to the PU and TPR glue-bonding.

Mass production: The process of the present invention will significantlyincrease the productivity and efficiency of manufacturing process of thenon-peelable insole. The present invention eliminates the conventionalsteps of cutting the second layer to match with the first layer,aligning the second layer with the first layer, applying the gluebetween the first and second layers, and trimming the edge of the insoleafter the second layer is glued on the first layer. In other words, thepresent invention simplifies the entire process by only cutting thefirst layer and injecting the second layer on the first layer.Therefore, the present invention can save the production time andincrease the productivity.

Minimize manpower: The present invention can further minimize the laborcost of the non-peelable insole by simply using the injection machine.

Still further objects and advantages will become apparent from aconsideration of the ensuing description and drawings.

These and other objectives, features, and advantages of the presentinvention will become apparent from the following detailed description,the accompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a non-peelable insole according to apreferred embodiment of the present invention.

FIG. 2 is a perspective view of making the first layer of thenon-peelable insole according to the preferred embodiment of the presentinvention.

FIG. 3 is a top view of an insole mold of the method thereof accordingto the preferred embodiment of the present invention.

FIG. 4 is a sectional view of the insole mold according to the preferredembodiment of the present invention.

FIG. 5 is a sectional view of the insole mold according to the preferredembodiment of the present invention, illustrating the injection materialis being injected into a sealing cavity of the insole mold.

FIG. 6 is a sectional view of a non-peelable insole according to thepreferred embodiment of the present invention, illustrating a firstlayer and second layer integrally attached therewith to form the insole.

FIG. 7 is a flow diagram of a process of making a non-peelable insoleaccording to a preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

These and other objectives, features, and advantages of the presentinvention will become apparent from the following detailed description,the accompanying drawings, and the appended claims.

Referring to FIGS. 1 and 6 of the drawings, a non-peelable insoleaccording to a preferred embodiment of the present invention isillustrated, wherein the insole comprises a first layer 1 and a secondlayer 2 integrally and continuously formed with the first layer 1 in aglue-less manner, wherein the first layers 1 are preferably trimmed andcut from a first sheet, such as leather, rubber or the like, andembodied as PU material (polyurethane). The second layer 2 is preferablyformed via mold injecting process, so as to integrally and automaticallybond with the first layer 10, embodied as PU layer, via heat or meltingto form the bonding therebetween. Accordingly, the non-peelable insolepad can be a removable insole received in the shoe. Accordingly, thefirst layer 1 has a top surface for being contacted with a foot of awearer and a lower surface being integrally bonded with the second layer2. Preferably, the first layer 1 is made of non-leather material such asPU material. The second layer 2 has a shape in accordance with the firstlayer 1 and is heat-bonded on the lower surface of the first layer 1.Preferably, the second layer 2 is injected to the first layer 10 to formthe non-peelable insole pad, such that no glue is required to bondbetween the first and second layers 1, 2. Accordingly, the second layer2 is made of cushioning material for providing a cushion effect of thenon-peelable insole pad. In particularly, the second layer 2 is made ofTPR material. The second layer 2 is preferably formed by moldinginjection method, so as to integrally bonding with the first layer 1 toform the non-peelable insole pad. Therefore, the second layer 2 ispreferably formed by a fluid material as an injection material, whereinthe injection material is injected directly on the lower surface of thefirst layer 1, such that a secure bonding is formed between the lowersurface of the first layer 1 and an upper surface of the second layer 2.Accordingly the second layer 2 also has a bottom surface provided forcontacting with a bottom sole of the shoe, so as to be supported andaccommodated therewithin. It is worth mentioning that the upper andbottom surfaces of the second layer 2 are formed after the fluidmaterial of the second layer 2 is solidified.

More specifically, in order to manufacture the non-peelable insole, thepresent invention provides a process for making the non-peelable insolewhich comprises the following steps. First, cut a first sheet 3 to forma plurality of the first layers 1. Second, heat-bond the second layer 2on the first layer 1 to formed the non-peelable insole pad in aglue-less manner.

As shown in FIGS. 2 and 7, the step of cutting the first sheet 3, whichis preferably PU material, to form a plurality of the first layers 1 ofthe insole is provided. Accordingly, the first sheet 3 is cut to formthe first layers 1 having a predetermined shape for being able to beaccommodated within a bottom sole of a shoe. The first sheet 3 ispreferably made by a material of polyurethane (PU) and being cut to formthe first layer 1, wherein a graphic print, such as a predeterminedpattern, color, and/or texture, may be provided on the top surface ofthe first layer 1, such that the predetermined pattern, such as adesigned graphic, and texture may enhance the aesthetic appearance ofthe insole and create a smoothie and comfy texture for being contactedwith the foot of the wearer. It is worth mentioning the after the firstlayer 1 is cut from the first sheet 3, the graphic print will form onthe top surface of the first layer 1.

As shown in FIGS. 3 and 4 of the drawings, an insole mold 4 for makingthe non-peelable insole is illustrated, wherein the insole mold 4comprises a second molding body 41 as an upper mold body and a firstmolding body 42 as a bottom mold body to pivotally enclose with thesecond molding body 41 to form a sealing cavity therewithin of theinsole mold, which has a shape in accordance with a shape of the insole,wherein an injecting channel 410 is preferably formed at the secondmolding body 41 for communicating with the sealing cavity.

Accordingly, as shown in FIG. 4, following the step of cutting the firstsheet 3, the method further comprises a step of disposing the cut firstlayer 1 in the respective first molding body 42 of the insole mold 4,enclosing the second molding body 41 with the first molding body 42 toseal the sealing cavity of the insole mold, and placing an injectionmaterial, embodied as TPR material into an injecting device 5, as shownin FIG. 5. When the injection material within the injecting device 5 isfluidized, a step of injecting the injection material is started,wherein an injecting temperature during the injecting process ispreferably set between 150° C. and 300° C., so that the injectedinjection material will not damage the material structure of the firstlayer 1 while being able to securely attach with the first layer 1. Inother words, the fluid material of the second layer 2 is injected evenlyonto the first layer 1. Then, a shape of the fluid material is retainedto match with the first layer 1 until the fluid material of the secondlayer 2 becomes solid, so as to integrally form the second layer 2 onthe first layer 1. More specifically, the injection material ispreviously being heated to a predetermined temperature and liquefied forinjecting into an insole mold 4, such that a covalent bonding mayoccurred between the lower surface of the first layer 1 and the uppersurface of the second layer 2. Thus, the first and second layers 1, 2are integrally and continuously formed the non-peelable insole withoutany glue involved. The first layer 1 is directly bonded to the secondlayer 2 via the covalent bonding therebetween, which is a more secureand stronger bonding than traditional Van der Waals force between thefirst and second layers 1, 2 via glue.

After finishing the process of injecting the injection material into theinsole mold 4, the finished insole formed by the first layer 1 and thesecond layer 2 of the injection material is able to be removed from theinsole mold when the temperature of the injection material is cooled toa predetermined temperature. The injection material for making thesecond layer 2 is preferably made by a material having the physicalproperties of both plastic and rubber, so that the second layer 2 isable to provide a predetermined hardness for supporting the first layer1 thereon, while having a predetermined flexibility for being bended forenhancing the comfortableness of the shoe with the insole. In thepreferred embodiment, the second layer 2 is embodied as a material ofthermoplastic rubber (TPR) for bonding with the first layer 1, so as toform the covalent bonding between the lower surface of the first layer 1and the upper surface of the second layer 2.

A step of trimming a peripheral edge of the finished insole may beprovided if the insole formed by the above mentioned injecting processhas imperfectly remaining injection material protruded at the peripheraledge thereof, so as to obtain a finalized product of non-peelableinsole.

Accordingly, the present invention is able to effectively enhance theproduction rate and to securely and evenly form the first layer 1embodied as PU layer with the second layer 2 embodied as the TPR layer.Therefore, the life time of the insole is significantly increased. Thepreferred TPR material used for the injecting process also meet theenvironmental standard. As will be readily appreciated that the TPRmaterial has the physical properties of both plastic and rubber, so thatit is TPR is preferably adapted as the injection material to form thesecond layer 2 in the mold injection manner. The TPR material is alsowell known as a material for easily processing via mold injection. It isappreciated by one skilled in the art that the TPR has widely adhesiveproperties for being easily adhesive with variety of materials, andgreat resistance of deformation while having a desired flexibility.Therefore, the second layer 2 made by the TPR material having thedesired flexibility also provides a cushioning properties of the insoleto enhance the comfortableness thereof. The resistance of deformation ofthe TPR increases the durability of the insole and provides a supportfor the first layer 10, so as to remain its position and shape thereof.

One of the advantages of the present invention is that the thickness ofthe second layer 2 is selectively adjusted by a volume of the fluidmaterial of the second layer 2. In comparison with the conventionalinsole, the thickness of the second layer 2 is fixed. As it is mentionedabove, the second layer 2 of the present invention provides thecushioning effect of the non-peelable insole pad. When the thickness ofthe second layer 2 is increased, the second layer 2 will provide bettercushioning effect of the non-peelable insole pad. Therefore, thethickness of the second layer 2 of the present invention can beselectively controlled by the volume of the fluid material of the secondlayer 2 injected on the first layer 1.

One skilled in the art will understand that the embodiment of thepresent invention as shown in the drawings and described above isexemplary only and not intended to be limiting.

It will thus be seen that the objects of the present invention have beenfully and effectively accomplished. The embodiments have been shown anddescribed for the purposes of illustrating the functional and structuralprinciples of the present invention and is subject to change withoutdeparture from such principles. Therefore, this invention includes allmodifications encompassed within the spirit and scope of the followingclaims.

1. An insole for being accommodated within a shoe, comprising a firstlayer and a second layer having a shape in accordance with said firstlayer, wherein said second layer is integrally and continuously formedwith said first layer to formed a non-peelable insole pad in a glue-lessmanner.
 2. The insole, as recited in claim 1, wherein said second layeris mold-injected on said first layer to form said non-peelable insolepad.
 3. The insole, as recited in claim 2, wherein said second layer isheat-bonded with said first layer to form said non-peelable insole pad.4. The insole, as recited in claim 3, wherein said second layer is bondwith said first layer to form said non-peelable insole pad through athermoplastic formation.
 5. The insole, as recited in claim 1, whereinsaid second layer is made of TPR material.
 6. The insole, as recited inclaim 4, wherein said second layer is made of TPR material.
 7. Theinsole, as recited in claim 1, wherein said second layer is made ofcushioning material for providing a cushion effect of said non-peelableinsole pad.
 8. The insole, as recited in claim 6, wherein said secondlayer is made of cushioning material for providing a cushion effect ofsaid non-peelable insole pad.
 9. A method for manufacturing anon-peelable insole, which comprises the steps of: (a) cutting a firstsheet to form a plurality of first layers; (b) heat-bonding a secondlayer on said first layer, wherein said second layer is integrally andcontinuously formed with said first layer to formed a non-peelableinsole pad in a glue-less manner.
 10. The method, as recited in claim 9,wherein the step (b) further comprises the steps of: (b.1) injecting afluid material of said second layer evenly onto said first layer; and(b.2) retaining a shape of said fluid material to match with said firstlayer until said fluid material of said second layer becomes solid, soas to integrally form said second layer on said first layer.
 11. Themethod as recited in claim 9 wherein, in the step (b), second layer isintegrated with said first layer through a thermoplastic formation. 12.The method as recited in claim 10 wherein, in the step (b), second layeris integrated with said first layer through a thermoplastic formation.13. The method, as recited in claim 9, wherein said second layer is madeof TPR material.
 14. The method, as recited in claim 12, wherein saidsecond layer is made of TPR material.
 15. The method as recited in claim10 wherein in the step (b.1), the injecting temperature is between 150°C. and 300° C.
 16. The method as recited in claim 14 wherein in the step(b.1), the injecting temperature is between 150° C. and 300° C.
 17. Themethod as recited in claim 10 wherein, in the step (b), said secondlayer is bonded on said first layer via an insole mold by a process of:disposing said first layer on a first molding body of said insole mold;enclosing said first molding body by a second molding body of saidinsole mold to define a sealing cavity between said first and secondmolding bodies, wherein said second molding body has at least aninjection channel communicating with said sealing cavity; and injectingsaid fluid material of said second layer through said injection channelinto said sealing cavity to evenly dispense on said first layer.
 18. Themethod as recited in claim 16 wherein, in the step (b), said secondlayer is bonded on said first layer via an insole mold by a process of:disposing said first layer on a first molding body of said insole mold;enclosing said first molding body by a second molding body of saidinsole mold to define a sealing cavity between said first and secondmolding bodies, wherein said second molding body has at least aninjection channel communicating with said sealing cavity; and injectingsaid fluid material of said second layer through said injection channelinto said sealing cavity to evenly dispense on said first layer.
 19. Themethod, as recited in claim 18, wherein a thickness of said second layeris selectively adjusted by a volume of said fluid material of saidsecond layer.
 20. The method, as recited in claim 19, wherein saidsecond layer is made of cushioning material for providing a cushioneffect of said non-peelable insole pad.